seat pressure switch

My 73 convertible has an interesting issue .... when the either or both doors are open ... key in the ignition or not one or both of the seatbelt pressure switches start to click rapidly, as if they are being energized off and on. Any ideas on what might be causing this ? I am in the process of cleaning up the interior floors under the carpet so I took the seats out today. None of the wiring or plugs look damaged, disconnected, corroded etc. I am not sure but I think this also occurred with the doors shut, but it was only the passenger side seat that was clicking. Thanks

Are you sure its the Seatbelt sensor? There is only one in the car and that's on the passenger seat. I am thinking that it might be the seatback release. As an option some cars had solenoid operated seat back releases that energized when the doors were opened. Verify if that is the case and we can continue to try to figure out what the issue is.

Are you sure its the Seatbelt sensor? There is only one in the car and that's on the passenger seat. I am thinking that it might be the seatback release. As an option some cars had solenoid operated seat back releases that energized when the doors were opened. Verify if that is the case and we can continue to try to figure out what the issue is.

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You may be right ... I noticed that the passenger seat had two seperate plugs that plugged into two different sets of wires going into the passenger seat. The drivers seat had two different style plugs, but only one was plugged into the driver's seat.

The noise I am hearing sounds more like a solenoid than anything else, and sounds the same in both seats. Don't know if this helps any ... thanks.

Are you sure its the Seatbelt sensor? There is only one in the car and that's on the passenger seat. I am thinking that it might be the seatback release. As an option some cars had solenoid operated seat back releases that energized when the doors were opened. Verify if that is the case and we can continue to try to figure out what the issue is.

Click to expand...

You may be right ... I noticed that the passenger seat had two seperate plugs that plugged into two different sets of wires going into the passenger seat. The drivers seat had two different style plugs, but only one was plugged into the driver's seat.

The noise I am hearing sounds more like a solenoid than anything else, and sounds the same in both seats. Don't know if this helps any ... thanks.

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Of interest both seats still have the lever you have to raise to tilt the seatback forward.

That's what I would expect to see for the wiring. Is your battery fully charged, a low battery could cause the issue you are seeing. There is one more option but I want to check the electrical schematics first to verify.

The seats with the solenoids still have the manual release. I assume a bad connection or dirty switch is preventing them from staying tripped while the door is open

Looking at the wiring, if your battery is good then there is a seatback relay that may be going bad. It's located in the glove box in the overhead. There is a flat plate with a few relays attached to it. Just remove a couple of screws holding the plate in place and then it can be lowered into the glove box opening. Make sure that the connections have not come loose. If that doesn't fix the issue it could be the relay going bad.

That's what I would expect to see for the wiring. Is your battery fully charged, a low battery could cause the issue you are seeing. There is one more option but I want to check the electrical schematics first to verify.

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The battery is fine as well as the charging system, I will double check the battery voltage tomorrow ... just to be safe. thanks

Looking at the wiring, if your battery is good then there is a seatback relay that may be going bad. It's located in the glove box in the overhead. There is a flat plate with a few relays attached to it. Just remove a couple of screws holding the plate in place and then it can be lowered into the glove box opening. Make sure that the connections have not come loose. If that doesn't fix the issue it could be the relay going bad.

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Thanks very much I will look into the relay and let you know what I find out ... might be a week or so as i have the interior/seats out of the car right now. Thanks again.

Looking at the wiring, if your battery is good then there is a seatback relay that may be going bad. It's located in the glove box in the overhead. There is a flat plate with a few relays attached to it. Just remove a couple of screws holding the plate in place and then it can be lowered into the glove box opening. Make sure that the connections have not come loose. If that doesn't fix the issue it could be the relay going bad.

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Hello,

I found the metal panel above the glove box and determined that all the connections were good and also determined that the "clicking" noise I was hearing was coming from one of the relays on the metal plate. what I also discovered was that the source of the intermttent clicking is the plunger style swithc in the passenger door that turns the interior lights on and off. I found this by pulling/shaking the wires that go to this switch would make the relay open and shut and the lights blink. When I unplugged the plunger switch the problem is gone. SO MY QUESTION ... IS THE PLUNGER SWITCH USUALLY BAD OR CAN THE PLUG /WIRING CONNECTED TO THE SWITCH USUALLY THE CULPRIT ? If I hold the swithc and move the plug/connector wires around it causes the short. WHAT WOULD BE THE BEST WAY TO DIAGNOSE THIS ? The plug/wires and switch all look to be in pretty good shape. I have enclosed some photos.

Normally, the plunger doesn't go bad, but they can. Easy enough to check: measure resistance between pins when the pin is out and plunged. Those switches are reproduced and relatively cheap.

Normally, the plunger doesn't go bad, but they can. Easy enough to check: measure resistance between pins when the pin is out and plunged. Those switches are reproduced and relatively cheap.

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Checked the plunger switch with an ohm meter, it is okay, cleaned it anyway with some contact cleaner. Cleaned the three prongs in the plug and applied some dielectric grease. Still shorting ... spread the prongs apart just a little for a tighter fit ... problem solved.

[voice of Mr. Burns]Excellent![/voice of Mr. Burns]